#include <fstream>

using namespace std;

ifstream fin("arbint.in");
ofstream fout("arbint.out");

const int NMAX = 4 * 100005 + 60;   //Maximul sirului
int N, M, Arb[NMAX];                //Variabile basic
int Val, Pos;                       //Valoarea si pozitia acesteia in sir
int maxim;
int start, finish;                  //Intervalul

void Update(int, int, int);
void Query(int, int, int);

inline int Max(int a, int b) {
    return (a > b) ? a : b;
}

int main()
{
    int X, A, B;

    fin >> N >> M;

    for(int i = 1; i <= N; i++) {
        fin >> X;
        Pos = i;
        Val = X;
        Update(1, 1, N);
    }

    for(int i = 1; i <= M; i++) {
        fin >> X >> A >> B;
        if(!X) {
            maxim = -1;
            start = A;
            finish = B;
            Query(1, 1, N);

            fout << maxim << "\n";
        }
        else {
            Pos = A;
            Val = B;
            Update(1, 1, N);
        }
    }
}

void Update(int nod, int st, int dr)
{
    int mid;
    if(st == dr) {
        Arb[nod] = Val;
        return;
    }

    mid = (st + dr)/2;
    if(Pos <= mid)
        Update(2 * nod, st, mid);
    else
        Update(2 * nod + 1, mid + 1, dr);

    Arb[nod] = Max(Arb[2 * nod], Arb[2 * nod + 1]);
}

void Query(int nod, int st, int dr)
{
    int mid;
    if((start <= st) && (dr <= finish)) {
        if(maxim < Arb[nod])
            maxim = Arb[nod];

        return;
    }

    mid = (st + dr)/2;

    if(start <= mid)
        Query(2 * nod, st, mid);

    if(mid < finish)
        Query(2 * nod + 1, mid + 1, dr);

}